New Delhi, Aug 12 (IANS) GMR Energy Limited Friday said it would acquire 30 percent stake in Indonesian firm PT Golden Energy Mines Tbk (GEMS) for $550 million, a move that would help it further enhance its coal assets.

"GMR Energy will be paying cash consideration of $450-550 million for the transaction funded through a combination of debt and internal accruals," the company said in a regulatory filing.

The acquisition, which will be made through an offshore special purpose vehicle domiciled in Singapore, is expected to close in 2011 calendar year.

As part of the transaction, GMR Energy has also entered into an offtake agreement with GEMS which entitles it to purchase coal over the next 25 years, with the annual offtake quantity steadily increasing to 10 million tonnes over the coming years.

"The acquisition of a significant stake by GMR Energy in PT Golden Energy Mines is a key milestone in the growth of GMR's energy business," said B.V.N. Rao, business chairman, GMR Energy.

"It will provide fuel security for our power plants under construction and also support further capacity addition and trading," he added.